Micrometer



Oct. 27, 1931. v. F. WH'TER ET Al.

MI CROMETER Filed May 12, 1928 Patenbted Oct. A27, 1931 UNITED STATESPATENT OFFICE VICTOR F. WITTER, F .AKROLLAND URBAN A. FREDERICK, OFFREMONT, OIEIIIO MICROMETER Application filed May 12, 1928.

This invention relates to dimension measuring instruments, andparticularly to those of the micrometer type.

The primary object of the invention is the provision of an instrument ofthe character described, which is simple and inexpensive in itsconstruction and is capable of a wide range of adjustment and also ofbeing used to accurately measure both the inside and outside dimensionsof articles.

The invention is fully described in the following specication, and whilein its broader aspect it is capable of embodiment in numerous forms apreferred embodiment thereof is illustrated in the accompanyingdrawings,

I in which,--

Figure 1 is a side elevation of an instrument embodying the inventionwith the parts arranged for taking outside measurements and with thebeam partly broken away.

' Figs. 2 and 3 are cross-sections on the lines 2, 2 and 3, 3,respectively, in F ig. 1, and Fig. et is a view similar to Fig. 1 withthe parts arranged for taking inside measurements.

Referring to the drawings, 1 designates a beam of any desired length,which is preferably of ruler form and is customarily graduated todesignate any desired units of measurement, such, for instance, asinches.

The beam 1 is provided with two laterally projecting arms 2 and 3 spacedlongitudinally of the beam and mounted for longitudinal adjustmentthereon.

Each arm 2, 3 is adapted to be rmly secured in adjusted relation to thebeam by a locking stem 4 which is mounted in the respective armtransverselj.7 of the beam and has'one end provided with a foot lug 5for engaging in a groove 6 provided in one side 40 of the beamlengthwise thereof. The other end of such stem projects into an opening7 in the associated arm and has a nut 8 threaded thereon within suchopening and shouldering against the top of the beam, whereby atightening of the nut causes it to cooperate with the stem to clamp thearm in adjusted relation to the beam.

The arm 2, in the present instance, is provided on one side thereof inoutwardly spaced relation to thel beam 1 with a micrometer Serial No.277,153.

adjusting head 10, which projects transversely from the arm lengthwiseof the beam and toward the other arm when the parts are arranged fortaking outside measurements, as shown in Fig. 1. This micrometer headmay 5'5 be ot' any term and construction suitable for the purpose, andmany types of such head are commonly sold on the market. This v headcomprises, in the present instance, a part 11, which is stationary withrespect to the arm 2, and a work engaging part 12, which is adjustablymounted on the part 11. Such adj ustment is customarily of a rotaryscrew type. The other head 3 of the pair is provided in opposition tothe micrometer head 85 10 with a work abutting part 13, which may bemounted in the arm 3 to permit adj ustmentto compensate for wear, such,for instance, as providing the abutment 13 with a stem which is threadedin to the arm.

t is apparent that in the use of the instrument for taking outsidemeasurements of an article, one or both of the arms 2 and 3 may beadjusted on the beam 1 to render the distance between the micrometerhead 10 and 75 abutment 13 substantially that of the size of the part tobe measured, after which the micrometer head is adjusted to cooperatewith the measurement designations on the beam to correctly determine andindicate the desired outside dimension of the article.

For taking inside measurements of an article, such, for instance, as acylinder, the arms 2 and 3 are placed on the beam in reverse order tothat shown in Fig. 1, so that the micrometer head 10 and work abutment13 are disposed away from each vother and at the outer sides of therespective arms, as shown in Fig. L1. The arms having been arranged inthis manner on the beam, the correct measurement of the inside diameterof an article is obtained in the same general manner as above stated forobtaining outside dimensions.

To facilitate a step adjustment of the arms 2 and 3 on the beam and torigidly brace the arms against movement in opposed direction on the beamfrom that in which the measurement is being taken, each arm is providedwith a spring-pressed pawl 14, which may be engaged with any one of aplurality of suitably spaced notches 15 on the edge of the beam adjacentto thel pawls. These notches v l are disposed on both edges of the beam,those on one edge being disposed to prevent outward movements ofthe dogsand associated Y armsrvvhenf.- engaged therewith, as., shown in Y thearrangement clit-Fig. ,1,fandethe fnotches .1 on the otheredge ofthebeam being disposed l j to prevent inward movements of the pavvlsand-fassociated'f-arms vvhen-thepavvls-#arein engagement therewith, asshown by the arrangement in Fig. 4. It is preferable tohav'e the notchesof each set Vequidistantlypaced a predetermined unit of measurementapart.

y l-fsuchfunit offmeasurement'isone inch, .the

:micrometer `head-l0,fshouldhave apermisf sible adjustment within arange of oneinch ff Wevvish it funderstood r`that'lourinvention i l530is not-limitedtdany speciiioconstruction, ar-

Y --frangementorfform of-the parts, as it is'ca- @pablefl of embodimentinv numerous forms i'yvithout departing from-.fthey spirit, of "ther,Claim. I f

125 :Having ,th-.us ,described our invention; What -We claim v'as newand desire to secure by :Let-

ters-Patent is: y Y v Y In an instrument of the, lclass described, abeamhaving aseries of notches along one ,edge andfhaving a longitudinalgroove in VOne efacellthereof, a-Spairof arms proj ectin'g lat-Vei-ally-from-the beam,;at least one of saidfarms .being adjustable;lengthwise of; thel beam, a' pavvlfl carried', byiVv said` adj ustable j`arm and 3,5 selectively engageabler ,'vvithffsaid.; notches todetermine'thewposition of adjustment of -1- said arm l relativetofsaid 1beam, arthreaded e ll'loclingl-stem' carried vbyisaidadj ustabley armland A disposed longitudinally; thereof, :said 40j`adj usta'blej armbeingy providedin its-*facce ad# -rjacentethe beam'vvith aggroove inlWhich fthe locking-stem lits, alug on said stemextendinginto-thewgroove'inthe beam, a nutth'read- Y Y ed. on ,fthe stem-aand;having a shoulder' op- Y to bringthe shouldenintoengage-ment-with asunface ofthe. beam-,I-.said lug-and? saidvjshoul- .ederlcooperatingztoclampthe arm tothe beam,

. and a imicrometer:headcarried by one 4oit: said :'50farmsandcooperating Withathe other armforVobtainingpreciserllleasurements.

In testimony :whereof We v have hereunto signedflour 'names togthisspecification. VICTOR FyWITiTER.

1 V.f ,QURBANFREDERICK.

